Prevalence and prognostic impact of chronic kidney disease and anaemia across ACC/AHA precursor and symptomatic heart failure stages

BACKGROUND

The importance of chronic kidney disease (CKD) and anaemia has not been comprehensively studied in asymptomatic patients at risk for heart failure (HF) versus those with symptomatic HF. We analysed the prevalence, characteristics and prognostic impact of both conditions across American College of Cardiology/American Heart Association (ACC/AHA) precursor and HF stages A-D.

METHODS AND RESULTS

2496 participants from three non-pharmacological German Competence Network HF studies were categorized by ACC/AHA stage; stage C patients were subdivided into C1 and C2 (corresponding to NYHA classes I/II and III, respectively). Overall, patient distribution was 8.1%/35.3%/32.9% and 23.7% in ACC/AHA stages A/B/C1 and C2/D, respectively. These subgroups were stratified by the absence ( - ) or presence ( +) of CKD (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73m2) and anaemia (haemoglobin in women/men < 12/ < 13 g/dL). The primary outcome was all-cause mortality at 5-year follow-up. Prevalence increased across stages A/B/C1 and C2/D (CKD: 22.3%/23.6%/31.6%/54.7%; anaemia: 3.0%/7.9%/21.7%/33.2%, respectively), with concordant decreases in median eGFR and haemoglobin (all p < 0.001). Across all stages, hazard ratios [95% confidence intervals] for all-cause mortality were 2.1 [1.8-2.6] for CKD + , 1.7 [1.4-2.0] for anaemia, and 3.6 [2.9-4.6] for CKD + /anaemia + (all p < 0.001). Population attributable fractions (PAFs) for 5-year mortality related to CKD and/or anaemia were similar across stages A/B, C1 and C2/D (up to 33.4%, 30.8% and 34.7%, respectively).

CONCLUSIONS

Prevalence and severity of CKD and anaemia increased across ACC/AHA stages. Both conditions were individually and additively associated with increased 5-year mortality risk, with similar PAFs in asymptomatic patients and those with symptomatic HF.

P2612Anaemia and renal impairment in heart failure: prevalence and differential prognostic importance according to the AHA ACC heart failure classification

Background

Anaemia (A) and renal impairment (RI) are frequent comorbidities in heart failure (HF) and known to impact adversely on outcome.

Purpose

In this post-hoc analysis, we allocated HF patients from 4 studies of the Competence Network Heart Failure at baseline to subgroups according to American Heart Association/ American College of Cardiology (AHA/ACC) HF criteria and compared prevalence rates of A and RI at each HF stage and the individual and cumulative long-term impact of these comorbidities on all-cause mortality (ACM) over a 5-year follow-up (FUP) period.

Methods

To study A and RI prevalence, we performed a cross-sectional analysis in 3344 patients (40.6% female, 65.6±11.2 years, 7.8, 32.3, 38.5, and 21.4% in stages A, B, C1 and C2/D, respectively). FUP data were available for 2496 patients (37.4% female, 66.0±11.3 years, 8.1, 35.3, 32.9, and 23.7% in stages A, B, C1 and C2/D, respectively). A was defined as haemoglobin <13/12 g/dL in men/women and RI as estimated glomerular filtration rate <60 mL/min/1.73m2. Within each HF subgroup, participants were divided in those without these comorbidities (A-/RI-), with either A or RI (A+/RI- and A-/RI+), or with both, A and RI (A+/RI+). For survival analysis log rank tests and multivariable Cox regression models were used.

Results

Overall prevalence of A in the stages A, B, C1, and C2/D was 3.1, 7.6, 16.5, and 29.8% (p<0.001) and of RI 17.6, 21.3, 24.4, and 46.6% (p<0.001), respectively. In the 4 subgroups, prevalence rates of A-/RI- were 80.2, 74.3, 66.3, and 42.1%, (p<0.001). A+/RI- and A-/RI+ were present in 2.3, 4.4, 9.3, and 11.3% (p<0.001) and 16.8, 18.1, 17.2, and 28.1 (p<0.001). A+/RI+ was found in 0.8, 3.1, 7.1, and 18.5% (p<0.001). Kaplan Meier curves demonstrate the individual and cumulative prognostic impact of A and RI (Figure).

Conclusions

Our results demonstrate a high prevalence in particular of RI even in asymptomatic HF stages and significant individual and cumulative long-term adverse effects of A and RI across the entire HF continuum. This includes also the clinically asymptomatic HF stages. Both prevalence and the individual and cumulative negative prognostic impact increase with increasing HF severity calling for careful consideration and management of these comorbidities in the frame of holistic HF care.